The National Zoo says a female red panda has been euthanized at a conservation center in Virginia after suffering brain swelling associated with a microscopic parasite.

The 7-year-old red panda named Shama died Saturday. She became well-known at the zoo as the mate of Rusty. He escaped the National Zoo last year. Shama gave birth to three cubs earlier this summer but developed a brain disorder that quickly progressed.

Shama, Rusty and the cubs were housed at the Smithsonian Conservation Biology Institute in Front Royal, Virginia.

Zookeepers say Shama’s three cubs are now being hand-reared by animal keepers. The cubs are active, but one is smaller than the others and is being treated for pneumonia.